A supporting disk of this kind is known from the German Patent DE 41 36 793C1. The hub ring is peripherally surrounded by the supporting ring which directly adjoins it. The hub ring is made of a polymer material which has a modulus of elasticity of 7,000 to 13,000 N/m2, a heat-distortion temperature of 150° C. to 250° C., as well as an elongation at fracture of 1.3% to 3%. A supporting disk of this kind is simple and inexpensive to manufacture. It should be noted in this context, however, that, during normal operational use and under conditions of high mechanical stress, such as in fulling processes, the temperature prevailing in a supporting member made of a polymer material can increase to the point where it becomes thermally damaged.
Another supporting disk is known from the German Patent Application DE 40 11 632A1. In this supporting disk, the hub ring is made of a metallic material, which is less than satisfactory from a standpoint of production engineering and economics. The hub ring must undergo a relatively complex pretreatment before being joined to the supporting ring made of polymer material.
Another supporting disk used to provide bearing support to a rotor of an open-end spinning machine is known from the German Patent DE 100 46 525 C2. The hub ring is designed as a composite part and is made of at least two different materials, i.e., of a metallic and a polymer material which are joined together non-positively and/or positively. The hub ring is formed from a disk made of aluminum which is at least partially covered by a plastic casing. Mechanical claw-type interlocking forms a durable connection between the aluminum disk and the plastic casing. The previously known supporting disk exhibits good thermal conductivity and high mechanical strength properties.